Abstract- Literature 1
Edible oil refinement is one of the major problems faced by the developing countries across the world as edible oil effluents are a major source of environmental pollution. Owing to this, it is essential to ensure that the effluents are treated prior to its disposal. The composition, characteristics and quantity of the waste water generated depends on the operating conditions and processes followed and can vary from different organizations in the same industry. An investigative method comprising of an in-depth study of unit operations, monitoring, measurement and analysis of parameters affecting environment, and performance evaluation of utilities and pollution control devices showed that the amount and composition of the effluents varied considerably. The high organic matter content is a basic problem, but the organic compounds are biodegradable and can be treated by adopting the conventional aerobic biological methods. The different methodologies available for the effluent treatment are 1) Refinery Effluent Treatment - The wastewater from the refinery and acid oil recovery plant are treated in the existing effluent treatment plant, 2) Biological Aeration Process and 3) Sludge Treatment. The parameters monitored include p H, total suspended solids, oil & grease, COD and BOD. The studies conducted concluded that for an effective treatment of edible oil waste, a biological treatment process is recommended, in addition to the chemical and biological methods in order to reduce the presence of biodegradable organic content and thus improve the quality of the final effluent .
Abstract-Literature 2
The problems of pollution and waste water generation are more pronounced in tourist locations like Hisarya, where a large number of tourists visit during the peak season. In such places where the industrial chemical waste and biological wastes produced by the households coalesce, waste water treatment poses a big problem for the authorities. The operation of a wastewater treatment plant in the town of Hisarya was studied by monitoring the values of the input and output water. This paper focuses on the efforts taken to evaluate the performance of the wastewater treatment plant in Hisarya including biological stage in aeration basins of cyclic type. The operation of the WWTP was evaluated using the indicators- COD, BOD5, total nitrogen, total phosphorous and suspended solids. The input and output results were evaluated with the standards defined for these stages. The results of the treatment exhibited significant differences in the input and output values and the pollution level was even less than the standard values set for the effluents. The effects of the biological treatment of the wastewater for the Hisarya WWTP plant were established and were proved that the plant operates well within the regulations as the values were significantly below the standard emission limits .
Abstract- Literature 3
This paper focuses on the investigation of physiochemical treatment of vegetable oil refinery wastewater (VORW) or acid and technological wastewater. At every stage of the oil refinement processes, by-products and wastes are formed. The composition, characteristics and quantity of the waste differs from one oil industry to the other and are dependent on the operating conditions and operating processes. The treatment of wastewater, in spite of adopting the latest biological, chemical and physical methods remain a challenge mainly due to the complexity involved at the source of production. Owing to this complexity involved, standardization of waste-water treatment remains as a challenge. The parameters considered for this study to evaluate the physiochemical process and assess the biodegradability of the treated wastewater include the PH, oil and grease, suspended solids and organic constituents (COD and BOD5). The investigations were carried out using the samples of untreated and treated wastewater samples with the inputs into the plant as technological and acid wastewater. In the technological wastewater treatment process, coagulation, flocculation and dissolved air floatation methods are the most critical processes. These methods ensure the removal of suspended matter and organic matter through colloid destabilization and organic adsorption into floes. BOD and COD were reduced by 25% and 20% respectively, whereas sulfates, phosphates and chlorides were reduced in varying amounts, even though their concentration in the influx was similar. This shows that the physiochemical treatment method is good in removing suspended solids and solvent extractable than BOD or COD. The acid wastewater treatment process deals with the removal of sulfate and phosphate ions, fatty materials and organic suspensions. The chemical process is more efficient in the removal of suspended solids, solvent extractable, sulfates and phosphates. For BOD and COD, a biological treatment process may have to be adopted to improve the final effluent quality .
Abstract-Literature 4
This paper talks about Sequencing Batch Reactor (SBR) in detail, including the SBR process, design concept, operational and maintenance aspects and case studies. SBR, an upgraded version of the conventional activated sludge process (ASP) is a fill and draw activated sludge treatment system that is time oriented and involves sequential processes in the same tank. The difference between SBR and the conventional ASP is that the SBR carries out functions such as equalization, aeration and sedimentation in a time sequence, rather than space sequence in the ASP, allowing SBR with the advantage of flexibility in operation. Owing to this advantage, the same SBR plant can be operated either as a labor intensive, low energy and high sludge yield system or as an energy-intensive, low labor and low sludge yield system. It also enables the designers to meet multiple treatment objectives like BOD and suspended solids reduction at one time and nitrification in addition to BOD reduction at another time. The SBR system consists of multiple reactor tanks operating in parallel. The operating cycle of an SBR reactor consists of five phases- fill, react, settle, draw or decant and idle. The number of parallel SBRs is determined by the influent flow rate. For a larger and continuous waste stream, multi-tank systems will be more appropriate, whereas for small establishments like schools, amusement parks, office complexes, a single tanks SBR system will meet their requirements .
Abstract- Literature 5
The article ‘Wastewater Technology Fact Sheet’, published by EPA talks about Sequencing Batch Reactors (SBR), which is a fill and draw activated sludge system for wastewater treatment. Equalization, aeration and clarification can be performed by a single batch reactor and can be used in multiple areas like the treatment of municipal waste, industrial waste, etc. Very similar to an activated sludge system, SBRs have been in use since the early 20th century. The difference between the SBR and the active sludge system is that, SBR adopts a time system rather than space sequence as in active sludge system. SBRs are typically deployed at the flow rates of 5MGD or less. For plants with large flow rates, increased sophistication is required, which is generally discouraged. Owing to its design, SBR suits well for areas where land availability is limited. Also, the cycles within the system can be modified for nutrient removal, if required. In short, SBRs are very flexible in operation and are very cost effective. Some of the major advantages of SBR include flexibility in operation and control, minimal footprint, capital cost savings, ability to achieve multiple functions in a single vessel. The major drawbacks include the requirement of added sophistication for larger systems, higher maintenance levels, potential of discharge floating and plugging of aeration devices, potential requirement for equalization etc. Some of the key design parameters adopted for the SBR include food to mass, treatment cycle duration, typically low water level mixed liquor suspended solids, hydraulic retention time, etc. The five phases of SBR include idle, fill, react, settle and draw .
References
Anon., 2001. Limits of Physicochemical Treatment of Wastewater in the Vegetable Oil Refining Industry. Polish Journal of Environmental Studies, 10(3), pp. 141-147.
Environmental Protection Agency, 1999. Wastewater Technology Fact Sheet- Sequencing Batch Reactors, Washington D.C: US EPA.
S. Vigneswaran, M. S. D. C., n.d. Sequencing Batch Reactors: Principles, Design/Operation and Case Studies. Encyclopedia of Life Support Systems.
Sarita Sharma, A. K. S. S. V. H. S. D., 2014. Edible oil refinery waste water treatment by using effluent treatment plant. International Journal of Chemical Studies, 2(3), pp. 36-42.
Tsvetko Prokopov, D. M. N. M., 2014. Biological Treatment of Wastewater by Sequencing Batch Reactors. ECOLOGIA BALKANICA, 5(Special Edition), pp. 33-39.
